AQA GCSE Combined Science Foundation (8464), Foundation tier · Chemistry › Chemical analysis › Purity, formulations and chromatography
Practise Formulations. 7 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
A formulation is a mixture designed as a useful product, with each component there for a reason. Questions ask you to recognise formulations, suggest what a component does from the information given, and do simple mass or percentage calculations.
Key facts
Formulation = a mixture that has been designed as a useful product
Each component has a particular purpose
Components are mixed in carefully measured quantities so the product has the required properties
All the percentages in a formulation add up to 100%
Notes
What a formulation is
A formulation is a mixture that has been designed as a useful product.
Each component has a particular purpose (job) in the product.
The components are mixed in carefully measured quantities so that the product has the properties it needs.
A formulation is a mixture, so it is not a pure substance. Changing the amounts of the components changes how the product behaves.
Examples
Formulations include fuels, cleaning agents, paints, medicines, alloys, fertilisers and foods.
Paint: a pigment gives the colour, a binder sticks the pigment to the surface, and a solvent makes the paint runny enough to spread, then evaporates.
Medicine tablet: the active ingredient treats the illness; other components bulk out the tablet, hold it together, improve the taste or control how fast it dissolves.
Alloy: steel is iron mixed with set amounts of carbon (and sometimes other metals) to give it the hardness and strength needed.
You do not need to learn the ingredients of branded products. The question gives you the information you need.
Formulation calculations
diagram
Mass of a component = (percentage ÷ 100) × total mass.
Percentage of a component = (mass of component ÷ total mass) × 100.
The percentages of all the components add up to 100%, and the masses add up to the total mass.
Each component has a job; mass = percentage ÷ 100 × total mass.
Keep the units the same: all in g or all in kg.
How to answer each type of question
Recognise formulations
1 to 2 marksGrade 3
Use the definition: a mixture designed as a useful product.
Rule out single elements and compounds, such as helium or pure water: they are not mixtures.
Example. Which two of these are formulations? A fertiliser B helium C sodium chloride D washing-up liquid E iron
Show the model answerHide the model answer
A (1) D (1)
Explain why the components are carefully measured
2 marksGrade 5
Say that each component has a particular purpose in the product.
Say that the correct amounts give the product the properties it needs, so it works as intended.
Example. A company makes a hand-cleaning gel. The gel is a formulation. Explain why the company must measure the amount of each component carefully.
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Each component has a particular job in the gel (1). The correct amount of each component gives the gel the properties it needs / makes sure it works properly (1).
Suggest the purpose of a component
1 to 2 marksGrade 5
Read the information for clues about what the product must do.
Link the component to a property of the product: colour, taste, strength, how it spreads, how it dissolves.
Give one clear purpose for each component asked about.
Example. A tablet for treating headaches contains a painkiller, starch, a sweetener and a thin, smooth outer coating. Suggest the purpose of: (a) the sweetener (b) the coating.
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(a) To make the tablet taste pleasant (1) (b) To make the tablet easier to swallow / to protect the tablet (1)
Don’t lose marks
Defining a formulation as just 'a mixture'. Say it is a mixture designed as a useful product.
Calling a formulation a pure substance or a compound. Its components are mixed, not chemically joined.
Saying the amounts are measured 'to make it safe'. The mark is for giving the product the properties it needs.
Mixing units in calculations, e.g. a total in kg and an answer in g without converting.
Forgetting to work out a missing percentage (100% minus the others) before finding a mass.
More tips
Memory tricks
A formulation is a recipe: chosen ingredients, in fixed amounts, each with a job.
The seven examples: 'Fresh Crisp Pizza Makes Anyone Feel Full' = Fuels, Cleaning agents, Paints, Medicines, Alloys, Fertilisers, Foods.
Sense check: the masses of the components must add up to the total mass.
10% is easy: divide by 10, then scale up (e.g. 30% = 3 × 10%).
Exam technique
Key phrases: 'mixture designed as a useful product', 'each component has a purpose', 'carefully measured quantities', 'required properties'.
In 'suggest' questions you are not expected to know the product: use the information in the question.
Show every step of a calculation and give the unit.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 3
Define a formulationA mixture that has been designed as a useful product.
Grade 3
Give examples of formulationsFuels, cleaning agents, paints, medicines, alloys, fertilisers and foods.
Grade 4
Identify formulations from given informationLook for a product made by mixing measured amounts of components, each with a purpose.
Grade 5
Explain why quantities are carefully measuredThe right amount of each component gives the product the properties it needs.
Grade 5
Suggest the purpose of a componentUse the information given, e.g. a pigment gives colour and a sweetener improves taste.
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
(a) What is a formulation? Tick (✓) one box.[1]
A mixture that has been designed as a useful product
A pure compound made in a laboratory
Any mixture of substances found in nature
An element that has been purified
(b) Which two of the following are formulations? Tick (✓) two boxes.[2]
Distilled water
Paint
Oxygen gas
Medicine tablet
Copper wire
(c) Formulations are made by mixing the components in carefully measured quantities. Give the reason why.[1]
Show the answer and mark scheme
(a)Answer: A mixture that has been designed as a useful product
(b)Answer: Paint; Medicine tablet
(c)
so that the product has the required properties / so each component can do its job
Question 2Medium5 marks
Paint is a formulation. {table} shows the components of one paint.
[object Object]
(a) Suggest the purpose of the solvent in the paint.[1]
(b) A tin contains 2.5 kg of the paint. Calculate the mass of pigment in the tin.[2]
(c) Explain why paint is described as a formulation.[2]
Show the answer and mark scheme
(a)
makes the paint runny / easy to spread / dissolves or carries the binder (and then evaporates)
(b)Answer: 0.55 kg
22 ÷ 100 × 2.5
0.55 (kg)
(c)
it is a mixture that has been designed as a useful product
each component has a particular purpose / the components are mixed in measured quantities to give the required properties